There are many people who suffer from having cold feet in winter, and others who suffer from having feet which are too warm and/or sweat during the summer. Many of these people attempt to treat such discomfort with a multiplicity of shoes designed for the different environments: warmer shoes for colder days and cooler shoes for warmer days. This has the potential to lead to excessive waste; for example, younger children often need shoes for one particular season and then grow out of them before they have a chance to wear them next season, leading to those shoes being discarded.
Additionally, there are health benefits to properly protecting feet, which may include properly regulating their temperature. Warming feet during the winter, for example, may help blood circulation and prevent or help recovery from colds or the flu. Overly warm feet in the summer can create a favorable environment for fungi or other microbes to grow in a warm and humid shoe. Footwear with insufficient cushioning can lead not only to pain in the feet, but also lower back pain, spinal stenosis, and some spinal cord problems. Various orthotics, including specially-designed footwear and inserts, exist to combat several of these conditions, but none satisfactorily deal with all of them.